“We had some [chances] with the score at 0-0,” said Mourinho. “Alexis had an open goal and then the countless opportunities of the last 20-25 minutes. The double [miss] of Martial is incredible in the last minute.”

The free-kick which led to Ritchie’s goal came when Red Devils centre-back Chris Smalling was adjudged to have dived.

Mourinho was reluctant to be too critical of the England international, saying: “A defender has to concede free-kicks now and again. It was an intuitive thing.

“Players who do it in the box deserve a card more than Smalling in that situation. Clearly I know we lost the duel in the air, and it’s difficult to accept that.”

Phil Jones, Smalling’s central-defensive partner, said the players were “devastated” by the defeat, which leaves them just two points ahead of third-placed Liverpool, who beat Southampton 2-0.

“We didn’t show up. We started slow. They pressed us, the crowd were on their feet,” said Jones.

“We got control midway through the first half and should have scored but we weren’t at the races. We weren’t good enough.

“Ultimately we have conceded a sloppy goal. The lads are devastated in the dressing room.”